Marine towing shackle

ABSTRACT

A U-shaped body including spaced apart generally parallel opposite side legs joined at one pair of corresponding ends by a generally semi-circular bight portion whose opposite ends merge smoothly into the adjacent leg ends. The legs are slightly convergent toward the other end thereof and include enlarged slightly angulated terminal end portions which parallel each other. The enlarged terminal ends of the legs are provided with aligned oval bores whose major dimensions extend in the plane of the U-shaped body and a pin which is oval in cross-section is removably secured through the bores.

United States Patent 15 3,656,293 Lowery, Sr. [451 Apr. 17, 1972 54] MARINE TOWING SHACKLE 125,744 4/1872 Low ..59/86 [72] Inventor: Archie J. Lowery, Sr., 500 Avenue J, Mar- 2 70072 2,420,256 5/1947 MacKenzie ..59/86 [22] Filed: Jan. 14, 1970 Primary Examiner-Charles W. Lanham PP 2,867 Assistant Examiner-Gene P. Crosby Attorney-Clarence A. OBrien and Harvey B. Jacobson [52] 11.8. C1 ..59/86 51 Int. Cl. .....F16g 15/06 [57] 4 ABSTRACT [58] Field of Search ..59/78, 86, 93, 85; 287/ 100; A U-shaped body including spaced apart generally parallel op- 24/116 R, 123 R, 201 R, 201 LP, 201 SL; 114/114; posite side legs joined at one pair of corresponding ends by a 294/82 R, 74, 75 generally semi-circular bight portion whose opposite ends merge smoothly into the adjacent leg ends. The legs are 56] R f e Ci slightly convergent toward the other end thereof and include enlarged slightly angulated terminal end portions which paral- UNITED STATES PATENTS lel each other. The enlarged terminal ends of the legs are provided with aligned oval bores whose major dimensions extend 2,709,616 Larson in the plane of the p y and a which is oval in 245,448 8/ l 881 Church "59/86 cross-section is removably secured through the bores.

48,844 7/1865 Shogren ..59/93 30,766 11/1860 Sigrist ..59/93 2 Claims, 4 Drawing; Figures PATENTEHAFR 18 m2 3,656,293

Arch/e J. Lowery, .Sr.

INVIiNTOK.

MARINE TOWING SHACKLE The shackle of the instant invention is designed for heavy duty use and primarily for the marine towing industry. The shackle includes a wide throat opening with generous inside dimensions that will allow passage of heavy duty hawser thimbles plus large synthetic rope thimbles that are normally used by the towing industry. The shackle is equipped with an ovalshaped through pin that offers more strength than a conventional round pin and is less likely to deform. In addition, the pin is secured by means of a split wedge cotter key in lieu of threaded nuts and thus the problem of galled threads is eliminated. In addition, the split wedge cotter pin key enables quicker removal and replacement of the through pin.

The legs of the shackle, except for their free end portions, are convergent and thus more resilient so as to more readily absorb sudden high stresses. Accordingly, the shock capacity of the shackle is greater than conventional shackles and the minimum ultimate strength of the shackle is four times its safe working load while its average proof load is twice the safe working load.

The main object of this invention is to provide a heavy duty shackle rated upwardly to 80 tons safe working load and yet constructed in a manner so as to maintain the weight of such a high capacity shackle at a minimum, on the order of 184 lbs.

Another object of this invention is to provide a marine towing shackle whose U-shaped body is of a configuration specifically designed to withstand heavy shock loads without taking a permanent set.

Yet another object of this invention, in accordance with the immediately preceding object, is to provide a marine towing shackle whose through pin is shaped in a manner affording greater strength and lessening the possibility of deforming.

A still further object of this invention is to provide a through pin utilizing a split wedge cotter pin as a means for securing the pin through the ends of the U-shaped body of the shackle whereby the possibility of galled threads which occurs on conventional shackles is eliminated.

A final object of this invention to be specifically enumerated herein is to provide a marine towing shackle which will conform to conventional forms of manufacture, be of simple construction and easy to use so as to provide a device that will be economically feasible, long lasting and relatively trouble free in operation.

These together with other objects and advantages which will become subsequently apparent reside in the details of construction and operation as more fully hereinafter described and claimed, reference being had to the accompanying drawings forming a part hereof, wherein like numerals refer to like parts throughout, and in which:

FIG. l is a perspective view of the shackle of the instant invention secured through a rope thimble and having the eye splice ends of a pair of cables engaged therewith;

FIG. 2 is an exploded perspective view of the shackle;

FIG. 3 is a plan view of the shackle;

FIG. 4 is a sectional view taken substantially upon the plane indicated by the section line 4-4 of FIG. 3.

Referring now more specifically to the drawings the numeral generally designates the marine towing shackle of the instant invention which is illustrated in FIG. 1 of the drawings as having a rope thimble referred to in general by the reference numeral 12 and a pair of cable eye splices 14 engaged therewith.

As can best be seen from FIGS. 2 and 3 of the drawings the shackle 10 includes a U-shaped body 16 including spaced apart generally parallel opposite side legs 18 and 20 joined at one pair of corresponding ends by means of a generally semicircular bight portion 22. The ends of the bight portion merge smoothly into the adjacent ends of the legs 18 and 20 and the leg are slightly convergent toward the free ends thereof and include enlarged slightly angulated terminal end portions 18' and 20. The enlarged end portions generally parallel each other and have oval bores or openings 24 fonned therethrpu The bores 24 are aligned and the shackle 10 further inc udes a through pin referred to in general by the reference numeral 26. The through pin 26 includes a shank portion 28 having an enlarged head 30 on one end and a transverse slot 32 fonned through the other end. The shank portion 28 is oval in cross-sectional shape so as to be snugly received through the bores 24 and a split wedge cotter pin generally referred to by the reference numeral 34 is provided and receivable through the slot 32 in order to secure the through bolt or pin 26 through the terminal end portions 18 and 20.

It is believed that it may be readily appreciated that the cotter pin 34 provides a means for securely fastening the through pin 26 through the end portions 18 and 20 and that the cotter pin 34 may be readily removed in order to remove the pin 26. Further, as may best be seen from FIG. 3 of the drawings the reversely curving portions of each leg of the body 16 extending between the central portion of the bight portion and the corresponding enlarged end. portion enables the legs 18 and 20 to flex slightly in response to sudden shock loads being applied to the shackle 10. This slight flexing does not result in any portion of the body 16 taking a permanent set and thus the shock load capacity of the shackle 10 is increased. Further, it will be noted that the major transverse dimension of the shank portion 28 is disposed in the plane of the body 16 and accordingly, the shank portion 28 of the pin 26 is stronger than the usual roundl pin and is less likely to deform when sudden shock loads are applied to the shackle 10.

It will be noted that the shackles 10 will be constructed of galvanized cast high strength alloy steel and that the construction of the shackle l0 enables the safe working load of an individual shackle to in some instances exceed 1 ton for every 2 lbs. of weight of the shackle.

The foregoing is considered as illustrative only of the principles of the invention. Further, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described, and accordingly all suitable modifications and equivalents may be resorted to, falling within the scope of the invention as claimed.

What is claimed as new is as follows:

1. A towing shackle comprising a U-shaped body including spaced apart legs joined at one pair of corresponding ends thereof by a generally semi-circular bight portion whose opposite ends merge smoothly into said one pair of ends, the other pair of ends of said legs being slightly convergent and including enlarged terminal end portions provided with aligned transverse bores, a through pin comprising an elongated shank having an enlarged head on one end removably secured through said bores, said terminal end portions being slightly angulated relative tosaid legs and paralleling each other, said bores being oval in cross-sectional shape with their major cross-sectional dimensions disposed in the plane of said U- shaped body and extending lengthwise of the corresponding legs, said shank also being oval in cross sectional shape throughout its length and snugly received through said bores, the other end of said shank including a transverse diametric slot which is generally rectangular in cross-sectional shape with its major transverse dimension extending lengthwise of said pin, said slot being disposed generally normal to the major cross-sectional dimension of said shank, and a split wedge cotter pin snugly and removably secured through said slot.

2. The combination of claim 1 wherein said bight portion and said legs, exclusive of said terminal end portions, are circular in cross-sectional shape. 

1. A towing shackle comprising a U-shaped body including spaced apart legs joined at one pair of corresponding ends thereof by a generally semi-circular bight portion whose opposite ends merge smoothly into said one pair of ends, The other pair of ends of said legs being slightly convergent and including enlarged terminal end portions provided with aligned transverse bores, a through pin comprising an elongated shank having an enlarged head on one end removably secured through said bores, said terminal end portions being slightly angulated relative to said legs and paralleling each other, said bores being oval in cross-sectional shape with their major cross-sectional dimensions disposed in the plane of said U-shaped body and extending lengthwise of the corresponding legs, said shank also being oval in cross-sectional shape throughout its length and snugly received through said bores, the other end of said shank including a transverse diametric slot which is generally rectangular in cross-sectional shape with its major transverse dimension extending lengthwise of said pin, said slot being disposed generally normal to the major cross-sectional dimension of said shank, and a split wedge cotter pin snugly and removably secured through said slot.
 2. The combination of claim 1 wherein said bight portion and said legs, exclusive of said terminal end portions, are circular in cross-sectional shape. 